This invention relates to a machine and method for automatically attaching a waist band to the bottom edge of a shirt and more particularly a rib knit waist band to a fleece sweat shirts.
This operation has traditionally been performed manually by a sewing machine operator. The operator was required to fold the band and load it on the sewing machine, load the shirt body and then manually guide the three edges during the sewing operation. The operator then manually chained off the garment, off loaded the garment and stacked the garment. This manual method is slow, expensive, wasteful of material, has a high rate of unacceptable products and places the operator under ergonomic stress and strain which is very fatiguing.
A method has been developed by Atlanta Attachment Company, in which the waist band and the shirt are loaded on rollers that can be pneumatically expanded. The garment pieces are automatically guided during the sewing cycle. Stitch counting from the beginning of the cycle is relied upon to signal when the garment is completed, after which the finished garment is automatically stacked. However, this method does not provide for individual material edge guidance and thus a relatively large edge ribbon of unequal width must be trimmed to assure that all edges will be stitched. In addition to wasting material this results in a waist band of unequal width and a finished product that does not have equal lengths around its periphery. Also in a method such as this, that relies upon stitch counting from the beginning of the cycle to signal when the garment is completed, a margin of error must be applied to the stitch count that will result in over-stitching of the beginning seam in most products. Furthermore there is no assurance that the edge guiders are actually functioning or that they are operating at a speed or feed that is synchronized with the sewing machine speed or feed.
For the foregoing reasons, there is a need for an automatic machine for attaching waist bands to the bottom edge of a shirt that independently guides each material edge and relies upon a method that senses the approach of the beginning seam as a signal from which completion of the garment is calculated. There is also a need for a machine of this type that has the ability to monitor the edge guiders to assure the operator that they are functioning and to synchronize the edge guiders speed and feed with the sewing machines such that waist bands having uniform width and garments having uniform length are produced.